Assessment of the Obesity Epidemic

More than 60% of US Adults Are Overweight

Flegal K, et al. JAMA 2002;288:1723-1727. Hedley AA, et al. JAMA 2004;291:2847-2850.

Obese (BMI ≥ 30)

Overweight (BMI 25 - 29.9)

Assessing Obesity: What Is BMI?

• BMI

– Calculated as weight(kg)/height(m2)

– Evaluates weight relative to height

– Replaced % ideal body weight as the primary criterion for assessing obesity

– Correlates significantly with body fat, morbidity, and mortality

NIH Natl Heart, Lung, and Blood Inst. Obes Res. 1998;6(suppl 2):51S.Willett WC et al. N Engl J Med. 1999;341:427.

Category BMI

Underweight < 18.5

Normal* 18.5 – 24.9

Overweight 25.0 – 29.9

Obesity ≥ 30.0

Class I 30.0 – 34.9

Class II 35.0 – 39.9

Class III ≥ 40.0

0

10

20

30

40

50

60

70

80

90

100

20 - 34 35 - 44 45 - 54 55 - 64 65 - 74 75 andOverAge in Years

% o

f M

ale

Pop

ulat

ion

.

ObeseOverweight

Flegal et al. JAMA 2002;288:1723-1727.

0

10

20

30

40

50

60

70

80

90

100

20 - 34 35 - 44 45 - 54 55 - 64 65 - 74 75 andOver

Age in Years

% o

f Fem

ale

Pop

ulat

ion

Obese

Overweight

Prevalence of Obesity by Age

Men Women

Obesity Trends by Gender and Ethnicity

28 29 29

0

10

20

30

40

50

60

White Men Black Men Mexican Men

Pre

vale

nce

of O

besi

ty

.

31

51

40

0

10

20

30

40

50

60

WhiteWomen

Black Women MexicanWomen

Pre

vale

nce

of O

besi

ty

.

Men Women

Flegal K, et al. JAMA 2002;288:1723-1727.

Flegal et al. JAMA 2002;288:1723-1727.

Education

Ave

rage

BM

I

22

23

24

25

26

27

28

1986

1988

1990

1992

1994

1996

1998

2000

2002

Year

No High School

High School

Some College

College

Income

23.0023.50

24.0024.5025.00

25.5026.0026.50

27.0027.50

Ave

rage

BM

I

198619

8819

9019

9219

9419

9619

9820

0020

02

Year

Lowest IncomeHighest Income

Prevalence of Obesity by Education and Income

Prevalence of Extreme Obesity (BMI ≥ 40) by Gender and Ethnicity

3.3 3.42.9

0

1

2

3

4

5

6

7

8

9

10

White Men Black Men MexicanMen

Pre

vale

nce

of E

xtre

me

Ob

esi

ty (

%)

5.5 5.7

13.5

0

2

4

6

8

10

12

14

16

WhiteWomen

Black Women MexicanWomen

Pre

vale

nce

of E

xtre

me

Obe

sity

(%

)

Men Women

Hedley AA, et al. JAMA 2004;291:2847-2850.

0

2

4

6

8

10

12

14

16

18

NHES II &III1963-70

NHANES I1971-74

NHANES II1976-80

NHANES III1988-94

NHANES1999-2002

Pre

vale

nce

of O

verw

eigh

t

.

Aged 6-11 years Aged 12-19 years

Prevalence of Overweight in Children and Adolescents

Flegal K, et al. JAMA 2002;288:1723-1727. Hedley AA, et al. JAMA 2004;291:2847-2850.

Coronary Heart Disease

Morbiditymortality

Morbiditymortality

Morbiditymortality

Hypertension Diabetes Dyslipidemia

40% are obese 80% are obese 50% – 70% are obese

OBESITY

Obesity and Coronary Heart Disease (CHD)

0

5

10

15

20

25

30

35

40

45

50

NHANES I1971-1975

NHANES II1976-1980

NHANES III1988-1994

NHANES1999-2000

% o

f P

op

ula

tio

n

.

Trends in Cardiovascular Risk Factors in Obese Individuals (BMI ≥ 30 kg/m2 )

Smoking

High Cholesterol

High Blood Pressure

Gregg EW, et al. JAMA 2005;293:1868-1874.

Diabetes

Obesity Is Caused by Long-Term Positive Energy Balance

Fatstores

Energyintake

Energyexpenditure

Regulation of Body Weight

• Genes confer the potential for obesity

• Environment determines whether and to what extent the potential is realized

Relationship Between Adoptee Weight and Weight of Biological or Adoptive Parents

Stunkard et al. N Engl J Med 1986;314:193.

Weight Classification of Adoptees

BM

I of

Par

ents

(kg

/m2 )

Thin Median Overweight ObeseThin Median Overweight Obese

Biological Parents Adoptive Parents27

21

26

25

24

23

22Fathers

Mothers

Heritability of Body Weight

Sedentary person

(1800 kcal/d)Physically active person

(2200 kcal/d)

60%

Components of Daily Energy Expenditure

32%

75%

8% 17% 8%

Thermic effect of feeding

Resting energy expenditure

Energy expenditure of physical activity

Decreased Energy Expenditures and Weight Gain

0 1 2 3 40

5

10

15

20

25

30

Cu

mu

lati

ve I

nci

den

ce o

f a

10-k

g B

od

y W

eig

h G

ain

(%

)

Time (years)

Low RMR Middle RMR High RMR

Ravussin E, et al. N Engl J Med. 1988;318:467-472.RMR = resting metabolic rate

Barsh GS, Schwartz MW. Nat Rev Genet. 2002;3:589-600.

Gene-Environment Interaction in the Pathogenesis of Obesity

Pima Indians inMaycoba, Mexico

Pima Indians inArizona

Ravussin E et. al. Diabetes Care 17:1067, 1994.

0

10

20

30

40

50 p < 0.0001

Body Mass Index (kg/m2)

The Toxic Environment

Food is…

• Highly accessible

• Inexpensive

• Advertised heavily

• High fat, high sugar

• Delicious

16 oz 32 oz 44 oz 52 oz 64 oz

1 oz ≈ 12 calories

Nielsen & Popkin, JAMA 2003.

Food Portion Size Trends

0

5

10

15

20

SaltySnacks

Desserts SoftDrinks

FruitDrinks

FrenchFries

Ham-burgers

Cheese-burgers

Pizza MexicanFood

Foo

d In

take

per

Ea

ting

Occ

asio

n,

oz

1977-19781989-19911994-1998

0

5

10

15

20

25

30

35

40

TV hours per day (youth report)

Pre

vale

nce

(%)

NHES 1967-1970

NLSY 1990

0 - 1 1 - 2 2 - 3 3 - 4 4 - 5 > 5

Prevalence of Obesity by Hours of TV per Day

NHES Youth Aged 12 to 17 in 1967-1970 and NLSY Youth Aged 10 to 15 in 1990

20%

43%

70%

80%

0

10

20

30

40

50

60

70

80

90

1969 1979 1989 1999

American Academy of Pediatrics.

% of Children withDaily Physical Education

Responding To The Obesity Epidemic

• Create a child-healthy environment

• Banish junk food from schools

• Reduce food ads directed at children

• Increase opportunities for physical activity

Psychological Factors and Obesity

• Moral problem?

• Psychological problem?

• Aesthetic problem?

• Social and medical problem?

Psychosocial Status of Obese Individuals

• Most obese individuals have normal psychological status

• Persons who seek weight loss report greater distress

• Patients at greatest risk of depression:– Women

– Extreme obesity (BMI ≥ 40 kg/m2)

– Binge eating disorder (BED)

Friedman & Brownell. Psych Bull 1995;117:3-20.

Risk of Major Depression with Extreme Obesity

Onyike, et al. Amer J Epidemiology 2003;158:1139-1147.

1.13 1 0.961.33

1.9

4.63

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

< 18.5 18.5 - 24.9 25 - 29.9 30 - 34.9 35 - 39.9 > 40

Body Mass Index (kg/m2)

Odd

s R

atio

Bodily Pain and Depression in Obese Individuals (N = 306)

0

2

4

6

8

10

12

14

16

18

20

40 - 49.9 50 - 59.9 60 +

Body Mass Index

Not Impaired

Impaired

Fabricatore AF. Obes Surg 2005; 15:304-309.

BD

I-II

Sco

re

Bodily Pain:

Prejudice Against the Obese

Six-year old children labeled silhouettes of an overweight child as:

Staffieri. J Per Social Psychol 1967;7:101.

•Lazy

•Dirty

•Stupid

•Ugly

•Cheats

•Lies

Prejudice Against the Obese

1961 20011

2

3

4

5

6

Mea

n R

ank

Healthy

Healthy*

Crutches

Crutches*Wheelchair

Wheelchair*

HandHand

Face

Face*

Obese

Obese*

Latner, JD, Stunkard, AJ. Obes Res 2003;11:454.

Discrimination Against the Obese

• Discrimination has been reported in:

– Student Selection

– Employee Selection

– Employee Pay and Promotion

– Tenant Selection

– Marriage

Roehling MV. Personnel Psychology 1999; 52: 969-1016.

Discrimination in the Workplace

−Discrimination against obese does not violate federal law in the US

−Title VII in US protects people from discrimination based on race, color, religion, sex, or national origin

−Obesity is not a protected characteristic

• Patients who lost 45 kg or more

• Preferred to be normal weight with a major handicap (deaf, dyslexic, diabetic, legally blind, bad acne, heart disease, leg amputated) than to be morbidly obese

• Rather be normal weight than a morbidly obese multi-millionaire

Social Stigma and Obesity: “I’d Rather Go Blind”

Rand CS. Macgregor AM. Int J Obesity 1991; 15:577.

Conclusion

• The epidemic of obesity is the result of a complex interplay of genetic, environment, cultural, and economic factors

• Greater efforts are needed to change the environment that lies at the heart of the epidemic

• Obese individuals should not be blamed for their condition, but instead be treated with respect, fairness, and compassion